A wireless communications technology may allow terminals such as a personal computer and a mobile phone to be connected in a wireless manner, facilitating people's life to a greatest extent, and the wireless communications technology has been currently widely applied.
A WLAN is usually used in a short-distance coverage scenario. The WLAN includes a wireless access point (also referred to as AP) and a station (STA). When a STA sends a signal, another STA may listen to the signal. If the STA that listens to the signal determines that a channel is busy, the STA keeps silent. An AP may properly receive the signal sent by the STA.
However, if a distance between STAs is relatively long or obstruction exists between the STAs, a STA cannot listen to a signal sent by another STA. In this case, two or more STAs may simultaneously send signals. Signals simultaneously received by the AP from a plurality of STAs interfere with each other, affecting proper signal reception of the AP.